diff --git a/revision.c b/revision.c
index cf5e6c1ec9..1c9934fb4d 100644
--- a/revision.c
+++ b/revision.c
@@ -2734,7 +2734,10 @@ void parse_revision_opt(struct rev_info *revs, struct parse_opt_ctx_t *ctx,
 {
 	int n = handle_revision_opt(revs, ctx->argc, ctx->argv,
 				    &ctx->cpidx, ctx->out, NULL);
-	if (n <= 0) {
+	if (n < 0) {
+		/* handle_revision_opt() has already reported the error. */
+		usage_with_options(usagestr, options);
+	} else if (!n) {
 		error("unknown option `%s'", ctx->argv[0]);
 		usage_with_options(usagestr, options);
 	}
diff --git a/t/t4201-shortlog.sh b/t/t4201-shortlog.sh
index 5f23fc147b..cde519402e 100755
--- a/t/t4201-shortlog.sh
+++ b/t/t4201-shortlog.sh
@@ -434,4 +434,10 @@ test_expect_success 'stdin with multiple groups reports error' '
 	test_must_fail git shortlog --group=author --group=committer <log
 '
 
+test_expect_success 'invalid revision options are not reported as unknown' '
+	test_must_fail git shortlog --default 2>err &&
+	test_grep "bad --default argument" err &&
+	test_grep ! "unknown option" err
+'
+
 test_done